How much solar to power the world?

Solar has been growing at an unprecedented rate across the U.S. and around the globe.

In 2015, over 7,000 megawatts of solar was installed in the U.S. That’s enough solar to power 1.1 million homes! The numbers show that solar is growing, fast—with no signs of slowing down.

That is great news for the environment and humanity because solar is the cleanest source of energy we have today.

Despite solar’s exponential growth, solar currently amounts to only 1% of Earth’s electricity production. How much solar would be necessary to power 100% of the Earth’s electricity needs?

Imagine that! A world completely free of emissions. No coal, no gas, no burning of fossil fuels.

A world powered entirely by the sun! Sounds like a great place for our children and grandchildren to grow up in, doesn’t it?

So, how difficult would it be? How much solar would the Earth need? Where could we find all that space?

The very first thing we have to figure out is:

How much power does the world use?

Humans use a lot of power, and our consumption goes up every year. By 2030, the U.S. Department of Energy projects energy requirements of Earth will reach 678 quadrillion Btus. A 44% increase from 2008’s world energy consumption.

The Land Art Generator Organization (LAGO) converted the world energy consumption BTUs into kW-hours, a unit most often used to describe quantities of electricity and the number is staggering: 192,721,800,000 kW-hours.

How much land would be needed for that?

LAGO divided the 192,721,800,000 kw-hours figure by 400 kW-hours of solar that 1 square meter of solar panels can produce. (Based on an assumption of 20% solar panel efficiency with 70% sunny days per year.)

According to those calculations, approximately 500 thousand square kilometers of solar panels are needed to power the entire world. That’s almost the size of Thailand!

Where could we find the space for all those panels?

The LAGO has also figured out where in the world we could fit all those panels! While using undeveloped land is easy to visualize, the vast majority of the panels could be placed on roofs of existing buildings.